1. Field of the Invention
The present invention relates to a golf club head and, more particularly, to scorelines in the face.
2. Description of the Related Art
In general, a plurality of linear grooves are formed in the face of a golf club head so as to run parallel to each other in the toe-to-heel direction (see, for example, Japanese Patent Laid-Open Nos. 10-248974 and 2005-169129). These grooves are called, for example, scorelines, marking lines, or face lines (these grooves will be referred to as scorelines in this specification). These scorelines have the effect of increasing the amount of backspin on a struck golf ball, or suppressing a significant decrease in the amount of backspin on a struck golf ball upon a shot in rainy weather or that from the rough.
Typically, as an angle θ of the side wall of the scoreline with respect to the face widens, the amount of backspin on a struck ball can increase but the golf club head is prone to scratch the ball at the same time.